Fair Value Measurements and Derivatives - Effects of foreign currency collar designated as cash flow hedges (Details 7) - USD ($) $ in Thousands |
12 Months Ended | ||
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Dec. 31, 2017 |
Dec. 31, 2016 |
Dec. 31, 2015 |
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| Designated as Hedging Instrument | Cash Flow Hedging | Foreign currency collar | |||
| Derivative Instruments, Gain (Loss) [Line Items] | |||
| Amount reclassified from accumulated comprehensive income (loss) into depreciation and amortization expense | $ (364) | $ (364) | $ (364) |
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. No definition available.
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- Definition The effective portion of loss reclassified from accumulated other comprehensive income into income on derivative instruments designated and qualifying as hedging instruments. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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